


Mate

by Jaspurr_Cat



Series: Grimmjow/Isshin Adventures [1]
Category: Bleach
Genre: Alternate AU - Werebeasts, Anal Sex, Heats, It's very indulgent, Knotting, Literally don't read if you don't like anything I mentioned in the tags, M/M, Master/Pet Dynamics, Mating, Mentions of Pregnancy, Sex Toys, Were-panther Grimmjow, owner/pet dynamics, this is just pure smut
Language: English
Status: Completed
Published: 2019-08-15
Updated: 2019-08-15
Packaged: 2020-09-01 08:17:55
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,620
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20255050
Author URL: https://archiveofourown.org/users/Jaspurr_Cat/pseuds/Jaspurr_Cat
Summary: Isshin adopts a feisty cat from the shelter. Set in a universe where were-animals exist as human/animal hybrids that are kept as pets or roam free in the world. Isshin is a human and Grimmjow is a were-panther. It's all smut.





	Mate

**Author's Note:**

> I have no excuses for this filth. Just read it and enjoy yourself. None of this was beta'd by anyone. If there's mistakes, oops.

To this day, he doesn't know why he had adopted his were-panther into his house. Isshin wanted a pet to have around since his son and daughters have gone their separate ways. In this strange world, there existed such pets as were-creatures for adoption or purchase depending on what kind of person you are. Somehow, he ended up at an adoption centre for them and met a few that took to him but he didn't really see an interest sparking for them until he saw Grimmjow. A black and blue were-panther with striking blue eyes that showed the opposite reaction to the others he saw. He was aggressive, feral, and absolutely stunning. In his mind, this would be a risky decision but he's always enjoyed a challenge.

He went through with it, taking home a way too violent cat that struggled to be friendly to anyone and especially his owner, expressing how he hated being owned and wanted to be free. Isshin doesn't attempt to cage him or anything though. He was free to go anywhere in the house and Isshin obliged to drive him places for food or new toys he wanted.

But the first real instance of submission that Isshin witnessed was when Grimmjow's heat had struck a couple months after he got him. The cat was full of energy and was just insatiable in the bedroom that Isshin started investing in sex toys that he could use if his owner couldn't help him. This was normal behavior for most pets that were kept and whether or not the owner wanted to do something about it was up to them. Isshin was just too generous of an owner sometimes. But since his first heat and Isshin being there to help him, Grimmjow's attitude has changed and he didn't want to harm Isshin at every possible opportunity.

This struck him as very odd and he took to the internet to find out what this could mean. Luckily there were reputable websites that talked about were-cat behaviour since most felines often exhibit similar habits and traits. He learned that when an owner or anyone really should help a were-creature through its first heat in the household, they'll be bonded and these pets are meant as forever pets. Isshin just put all of it together and assumed that Grimmjow had bonded to him and saw him not just as an owner but as a partner.

The thought sent him reeling back into reality, looking over his shoulder at the cat curled up on his bed and taking his nap. Well, looks like he's gonna be with this cat until he's dead. Maybe it wouldn't be so bad. If he can share a bed with him without being kicked off now, then it's fine.

* * *

It's been almost a year since Isshin has had Grimmjow in his household, finding the cat has significantly improved in behavior, acceptable enough to have his son and his family over without worry. He learned that the cat took to kids very easily, liking to play with them and distracting them so the adults can talk amongst each other.

And then with those times he had to help Grimmjow deal with his heats to the best of his ability. Every moment of it he cherished though. He's grown to love his cat very much that it was strange to say pet when it could be more like a partner or lover.

It was the middle of springtime. The season was rainy with higher humidity and Grimmjow usually was lazy during the season, napping more than anything. Then a week later, he struck heat as Isshin predicted. There's a certain cycle to it that he's figured out and knows exactly when to help his cat get over his need to mate and breed.

" Easy there, Grimmjow.. " Isshin cooed into his hair as he held the cat's body with one arm on his lap and pushed in one of Grimmjow's favorite knotted toys into him. It was nice that during these times, he produced his own slick at his entrance which mitigated the need for lube. He watched as those powerful legs kicked, squirming but the bigger male held him still.

He never would've thought that Grimmjow would be such a size queen to like having such monstrous toys. He's watched the cat pleasure himself on these before, sitting in his desk chair while the cat bounced his way to orgasm on some thick dildo, moaning and crying out for Isshin.

" M-More.. please… I want more, Isshin. " Grimmjow mewled weakly as he could feel the toy getting bigger towards the base. It was up until the fat knot that looked nearly impossible for somebody of Grimmjow's size to take but you'd be impressed.

Isshin was so hard watching this whole scene. Even being the one to insert the toy into him! " Slowly, baby… This is big even for you and you struggle still to take it. " He had a stern tone in his voice that made the cat under him shudder, his claws biting into the flesh on Isshin's thighs. Slowly, he pressed the toy in further as Grimmjow's slick hole strained against it, resisting the thick knot. He's whimpering underneath him and Isshin could only attempt to console him with praise and cooes. Eventually, his entrance gave way for the knot and Isshin pressed a little harder to get it to slip it inside and when Grimmjow was able to take it at the thickest point, he was able to push it all the way in until he's fully taken the knotting dildo into his body.

" I feel… full, master.. " Grimmjow purred so sweetly as Isshin pressed kisses to his head between his ears, moving his hand to cradling the cat in his arms. The palms rested on his stomach where a slight bulge could be seen. The stroking motions of Isshin's palm over his full belly made him purr, his tail swaying with delight between his legs as he reached his arms up now to hook them around Isshin's neck. " I want yer cock next… I bet ya have a lotta cum fer me, don'tcha? "

Isshin could never get used to the obscenity that spewed from his mouth in the bedroom. It almost made him want to fill it to make him learn his lesson for saying just vulgar things. But then Isshin would miss hearing it. He nibbled on the cat's sensitive ear as he squirmed from it, forcing the dildo to move that made the cat double over in his arms. " Hm.. If you behave and be a good boy, then I will fill you up with copious amounts of it during your heat and whenever you ask. " Maybe he spoiled him too much but fuck he's just so sexy that he found it hard not to spoil him a little.

Grimmjow chimed in with delight as he pushed himself up with the pads of his feet, squirming until Isshin let him go. He's more than aware of the toy in his hole and was glad for the knot to stop it from slipping out. " It would be nice if ya had a knot… Then ya can properly mate me, " Grimmjow draped himself on top of Isshin, pushing him down so that he was lying on top of him, chest to chest. " Imagine tha' bein' able ta have kids an' stuff but too bad, I can't carry em bein' a male of my species… " Maybe it was the heat talking because Grimmjow was just muttering things that he's never said before.

Isshin was surprised to hear those things but he understood that this was the purpose of his heats. To mate and breed children. Them being both males, it was hard to do so. It's impossible actually. Though the thoughts of it did rile him up if he could knock up his cat with his babies and they could have a family. It was.. strange to think about after his late wife but he knew she would understand and not be upset. She would want him to have closure and move on.

" It's an interesting thought I'll entertain now that you've said it, " Isshin reached a hand from where it sat on Grimm's lower back up to his face and tucked away a strand of blue hair from his face. " Do you want to have some fun with your toy before I fuck you silly and pump you full of cum? " Isshin smirked.

It wasn't shocking that he received a punch to his chest for it, seeing how he made his panther's cheek pink. He laughed before sitting up, supporting Grimmjow by his lower back with one hand and the other propped him up.

" ...Ya, I do.. The knot feels really good… Fuck me with the knot, please.. " Grimmjow looked up with pleading eyes that Isshin doesn't know how to resist. They just pull him in so much.

" Of course.. Give your master a kiss first. "

Grimmjow willingly obliged, leaning up to kiss Isshin on the lips. All the while that one hand trailed down to where it can grab the base of the dildo and pulled it out slowly. Judging by Grimmjow breaking the kiss to moan, it felt real good. The knot tugged at his hole as Isshin pulled it out until the bulbous knot popped out with a slick sound. " Fuck, you're so hot.. " Isshin growled out and Grimmjow shuddered.

" Lay on your back, legs spread apart and hold them. You're flexible enough. " He ordered next after pulling out the rest of the toy, leaving him empty and whining until he obeyed. Isshin moved so that Grimmjow can get comfortable in the position.

Seeing how his body folded so easily, his ass now on full display, he can see the work the toy had done on him. He was gaping and clenching around nothing, just air. It was absolutely sexy to see him so exposed. Isshin just wanted to lick around that abused rim, force his tongue inside and lap at his slick but he made a promise to his pet that he'd do this. " Are you ready? "

" More than ready, master… Maybe use lube if if needed. " 

_Good_ _idea_. Isshin reached over to the nightstand for the bottle of lube already sitting there, popping the cap and pouring some over Grimm's hole and then on the toy. The coolness of the liquid made him shiver. A finger on Isshin's hand slipped inside easily and pulled at his rim and Grimmjow keened. Moving on, he wiped his finger on his shirt and then lined up the toy to his hole. Slowly, he pushed it back in and marveled at how it just slid in up until the knot. " Here I go, " he announced before applying a lot more force than he had the first time to force the knot into Grimmjow's asshole. He could hear his moans, glancing up to see that his eyes were closed and his lips parted, tongue slightly poking out. And then he pulled it out, forcing it out as he made it go in. He repeated this over and over again, making Grimmjow take the knot until his hole just accepted the knot more easily. That's when he could not be so cautious and properly fuck his pet with the toy.

" Master! Master! " Grimmjow would cry endlessly as the knot rammed into his hole and out again. The pleasure was never ending as just when he thought it'd stop, the knot was either leaving his body or entering it with force. His arms were getting tired from holding his legs. At some point, his cock had came out of its sheath and was dripping precum all over his stomach and getting in his fur. Isshin finally slowed down when Grimmjow's orgasm hit him unexpectedly, shooting ropes of cum over his chest and some of it landed on his face. The panther was lying there, panting as his arms stopped holding his legs and he fell limp on the bed, attempting to recover. Isshin took the proper steps, first leaving to clean the toy and get a wet, warm towel to wipe down his panther with since baths were not going to be an opinion with how much Grimmjow hated them. Supporting his back with one arm, Grimmjow fell against him as he began to clean him up.

There was still the burning desire that Grimmjow had in him. It could never be satisfied even as he's came already once and felt a nap was in order. Curled up in Isshin's arms, he inevitably forced his master into a nap with him, dragging him down onto the pillows and fell into a slumber.

Isshin on the other hand was still dealing with an erection that he knew he couldn't deal with if he's stuck to Grimmjow. Waking him up would be a fatal mistake and trying to remove himself from him would be near impossible. The claws were too much of a threat if they weren't used to scratch at his skin when he's fucking him. Isshin sighed and resigned to lying there with Grimmjow curled up next to him and try to ward off his hard-on so that he can also sleep.

* * *

Isshin's eyes slowly fluttered open as he saw that the evening sun was casting light through the window. But there was something else amiss and also anew in this situation. Grimmjow wasn't at his side anymore and there's pressure between his legs… A mouth on him, a sandpaper tongue licking him. He pulled himself up to see and he guessed correctly when he saw Grimmjow perched between his legs, back arched with his rear up high. His hard cock was being held at the base by the panther, the rest of it sitting on his face where his tongue gave it soft licks.  _ Fuck, that's hot _ .

" Is this how you wake up your master? " Isshin hummed in a dazed voice, a hand reaching out to pet between his ears and grabbed a fistful of those long locks, tugging him upwards away from his cock. " You're a really naughty cat. I'm surprised you didn't try to fuck yourself on my cock while I was sleeping. "

" M-Master… " He mewled. " I need yer cock badly.. I woke up an' my body was hot.. I had'ta do somethin'. "

Isshin isn't pleased with his answer but dropped him down by releasing his hair. " Get me fully hard and then I'll fuck your little asshole until you're begging for me to stop. " For some reason, whenever he's woken up, he was more aggressive and dominating than usual. And this wouldn't be the first time that Grimmjow has done this to him. It became a pattern really. He liked it rough and Isshin would oblige though sometimes he liked it without needing to ask for roughness.

Grimmjow heeded his words, going immediately to jerking Isshin's cock with the one hand and lapping his greedy tongue at his slit. The taste of salty precum made him drunk and desire more but of course, he wanted to be fucked. He can get a mouthful of cum another time. He continued to stroke and lick his cock, occasionally giving the head soft sucks.

Isshin grunted and tugged Grimmjow away from his now fully hardened member, commanding him to get into whatever position he desired. It didn't matter as long as he was burying his cock all the way deep inside of Grimmjow's slick heat. He watched as the panther positioned himself in missionary position, even being whore-ish enough to spread his ass for the older male. " You're such a slut for this, aren't you? " Isshin growled, giving those cheeks a hard slap that made Grimmjow yell and jolt. " Baring to me your hole so willingly. Would you do this for anyone else? "

" No, I wouldn't think'a it. I don' want anyone else's dick but yers. " Grimmjow didn't skip a beat as he answered him, eyes looking up at him in all seriousness and sincerity. He was bonded to Isshin and he could never accept anyone else.

" Good boy. " Grimmjow keened at the praise.

" Your slick'll be enough, " he hummed as he looked at the already wet hole and smirked. He shuffled on over, taking hold of one of Grimm's legs and using the other hand to line his cock up to his hole. In one simultaneous thrust, he bottomed out inside of Grimmjow's body, the warm heat enveloping his cock so nicely.

" M-Master! Isshin! " Grimmjow cried from beneath him as he looked to where they were connected now. He saw how Grimmjow clenched around him, bringing the empty hand to trace around his rim. " This hole is so perfect.. For me. Only me. " He gave him shallow thrusts, wanting to take his time and properly make love rather than just fuck. Even though he said differently earlier.

He hushed Grimmjow when he said something, giving a hard glare down at the panther who was looking like he was going to lose it. He'll get his reward soon; he just had to have patience. Slowly, he moved both of his hands up Grimmjow's legs until he was gripping behind his knees. Using the leverage, he started to move. He would pull out and then snap his hips back in, making him cry out obscenities and his name each time. It was absolutely amazing to see how undone Grimmjow can get.

Isshin grunted every time he thrust inside of him. He focused on the both of them, making sure that Grimmjow was enjoying as much as he was enjoying. Leaning over, one hand coming down onto the pillows next to his head as he supported himself. Arms came up to wrap around his neck and pulled him down into a kiss. Isshin could feel the yearning and hunger in the kiss he shared with Grimmjow. It wasn't soft anymore like before. There were attempts to overtake the other, tongues clashing for some war of dominance. Isshin wouldn't let him win so easily, giving him a hard thrust that made his mouth open for him to slip his tongue into. Grimmjow would call it cheating but he was too lost in the pleasure to verbally complain.

Soon, Isshin fell into a constant, quick pace. The sounds of his hips hitting Grimmjow's ass filled the room. He couldn't stop himself now. This all felt too good for him and the panther's moans confirmed the other party. His weight was pressed against the other's body, forcing him to almost fold in half again. But with this angle, he can grind on Grimmjow's pleasure spots. Slamming into his prostate with every thrust that made the cat cry his name and spurred him on to keep fucking him until the end.

Nothing in the world could make him stop from pleasuring his partner until he's sated enough. Isshin went on, fucking him until he could feel the pressure in his balls. The hand that was once holding his leg had moved to the slit where Grimmjow's cock would come out of, fingering along the sensitive hole until he could coax his cock out and wrap his fingers around it to stroke. The added stimulation pushed Grimmjow over the edge to cum in his hand, Isshin fucking him through it until he came, shoving his dick as deep as he could and filled up his panther as he wished.

" There, baby… Take my cum.. " He cooed as Grimmjow whined with each spurt of warm semen that filled in body. The sensation of being filled was enough that he could ignore that there's no knot to lock them together. 

" K-Knot.. Keep cum… inside.. " Grimmjow panted, squeezing around Isshin's cock as his own retracted back into his body and seamlessly disappeared underneath the fur.

" Alright. " Isshin pulled out slowly, making sure that every drop was inside of Grimmjow before he got up to find one of the other knotted toys to plug Grimmjow up with. After some digging in the chest that was reserved for said items, he found a medium sized dildo with a sizeable knot. Climbing back onto the bed, Isshin saw a drop of cum slipping out and swiped it with his thumb and pushed it back in that made Grimmjow mewl weakly. Then he used the toy, pushing it slowly into his filled hole and promptly forced the knot inside so that it stayed. The things he does to keep the cat happy under his care.

He won't even lie that it's arousing to know that Grimmjow liked to be plugged up with cum inside until he no longer wanted to be. Isshin wiggled the toy around, making it push against his walls that made Grimmjow glare up at him from the overstimulation. He's typically very sensitive afterwards. 

" I'm sleepin' this shit off… " Grimmjow grumbled as he didn't bother to move from his spot on the bed though opting to flipping himself over on his stomach. The dildo was still inside of him and Isshin could only imagine how full he must feel.

" Don't sleep too long. I'm giving you a bath no matter what. " Isshin wasn't going to fight about this with Grimmjow tonight. A swat at his ass that jiggled the toy made the cat glare at him again over his shoulder. He huffed and used his tail to hide the crevice of his ass, tugging the duvet over himself even while Isshin could only watch how spoiled this cat really is.

First, he needed a shower before he would go make dinner, feed Grimmjow, and then bathe him. That was just day one of the week long heat cycle.


End file.
